An Optimal Diet in Promoting Nitrogen Gain in Nephrosis

Abstract

In the treatment of nephrosis Epstein 1 advocates a high protein diet, 150 to 200 gm., with low caloric intake. Peters and Bulger 2 from an investigation of the nitrogen metabolism in albuminuric, edematous patients conclude that it is possible to promote the storage of food protein and to cover the protein lost in the urine by allowing a moderate amount of protein in a high calory diet. The present study involves the determination of nitrogen balance and plasma proteins on 2 patients with nephrosis on diets which were varied in (1) total calories, (2) protein content and (3) proportion of animal and vegetable protein.

The first patient, 13 years old, had the nephrotic syndrome for 3 years before the study. He was in a state of convalescence at the commencement of this work which consisted of 47 periods of 4 days each, or 188 days. Weight at the start was 25.8 kg. With a constant protein intake of 50 gm. and 50% of animal protein, the caloric intake was raised (in steps of 280 calories) from 1750 to 2590 calories. The daily positive nitrogen balance, which averaged 3 gm., was not significantly altered. Progressive lowering of the caloric intake from 2590 to 1500 caused the nitrogen gain to lessen so that on 1500 calories the patient could hardly maintain nitrogen balance. He was then kept on 2310 calories, or approximately 75 calories per kg., while the protein content was raised. Feeding 75 gm. of protein resulted in an average daily nitrogen balance of 3.1 gm. as compared with 2.0 gm. on 50 gm. of protein intake, but further increase of protein intake to 100 gm. and then to 125 gm. did not promote any greater positive nitrogen balance.